Process for extracting nicotine from tobacco



May 17, 1938. R. J. HYATT I 2,117,558

PROCESS FOR EXTRACTING NICOTINE FROM TOBACCO Filed Aug. 20, 1956 EXTRACT canals/ism? RECEIV DISCHARGE 11,1 Hail Patented May 17, 1938 UNITED 'sTAT raocass FOR Ex'rnAc'rma NICOTINE mom 'ronnoco Robert J. and, Winston-Salem, N. 0., aseignor to R. J. Reynolds Tobacco-Company, Winston- Salem, N. 0., a corporation of New Jersey Application August 20. 1936, Serial N... 97,049

2. Claims. to]. s'z-zs) This invention relates'generally to processes for extracting nicotine and other volatile constituents of tobacco from tobacco wastes, such as stocks, stems, and low-grade leaves.

The main object. of the inventionisto provide a process to reduce the costs of extraction of nicotine from tobacco wastes, and to increase the i rate of extraction and percentage of recovery from such wastes.

In carrying out this process of extraction; the raw tobacco wastes are dried and ground, and otherwise reduced to a finely divided condition,

in order to expedite the chemical reactions involved in the practice of the process. This finely divided material is then mixed to saturation with an aqueous solution of soda; or is treated in any of the well-known methods with an alkali, such as hydrated lime, to free the nicotine from the other constituents of the tobacco waste. Preferably, the weight of the water used in the preliminary saturation is about equal to the weight of the tobacco waste undergoing treat- .ment, and the lime should be about ten percent ,of the weight of the tobacco wastes. The saturated alkaline'mixture is then charged into a drier, which may be a horizontal cylinder provided with the usual dry blender agitator. Heat is applied to the drier by a steam jacket, and the beaters are set in operation to ,efl'ect a thorough mixture of the saturated alkaline wastes and to yaporize the nicotine freed from such wastes. After a shortperiiod of this heating operation, the, nicotine-saturated vapor is with drawn from the drier through a dust filter to. a condenser by means ;of a vacuum pump.

The condensing operation is continued so long as liquid nicotine extract is disclosed as flowing from the condenser towarda receiver forming part of thestorage system. when the sight glass connecting the condenser and receiver shows that no more nicotine is flowing from the condenser.

to the receiver, the connection between the condenser and drier is closed. 1 Obviously, the interior of the drier,

dicates that the interior of thedrier'has again reached atmospheric pressure, the drier is closed originally a under atmospheric pressure, is then under vacuum. In this condition, most of the cells of the tobacco waste in the drier have'been exploded and have parted with their nicotine contents. However, many of such cells have not given up their nicotine content. In order to complete the extraction, the vacuum in the drier is broken as rapidly as possible to restore the pressure therein to at least atmospheric pressure. This increased pressure causes 'the unexploded cells to collapse. Just as soon as the pressure gauge inand the connection to the vacuum pump is again restored. I

The eifect of the suction applied by the vacuum pump again causes expansion of the unexploded collapsed nicotine cells, and causes more of the cells to rupture and part with their nicotine contents to the superheated steam already in the drier. This connection tothe vacuum system is .continued, so long as the sight glass at the output end ofrthe condenser discloses the passage of nicotine to the storage mechanism. When the sight glass discloses'that' the extraction of nicotine at this stage-has beenoompleted, the vacuum system is again disconnected, and the vac-" uum in the drier again brokensby the injection of steam thereinto. This subjection of the drier repeatedly to make and break the action of a vacuum, is continued until all-the nicotine. possible to be extracted from the waste has been extracted, as .determined by inspection of the condenser sight glass, after each application of the vacuum pump to the drier.

In carrying out of this process, it is essential, that the heat applied to the jackets of the driers and to the interior of the drier by the vacuum break system, shall begreat enough to prevent condensation in the drier. This evidently means that the steam used for'the' vacuum break must itself be dry and be of a temperature sufiiclent to prevent condensation in the heated drier.

The apparatus for carrying out this extraction provided with a jacket 4, connected to a valve controlled system 5 for conducting steam to said jacket. A valve controlled outlet pipe 6 is connected to the lower part of the jacket for the purpose of draining the same whenever found necessary or desirable. A pressure gauge 1 is mounted on the cylinder to indicate the pressure of the interior thereof and a charging manhole I is provided at the upper part for the purpose of introducing the material to be acted upon or processed. The lower part of the cylinder is provided with a series of manholes 9, II, and H, to

process is illustrated diagrammatically in the permit the removal of the spent tobacco waste from the cylinders.

A beater shaft I2 is mounted to rotate in the cylinder and is provided at one of its ends with a gear ll adapted to be connected to any suitable source of power to eil'ect rotation of the shaft. A series of beater blades ll are secured to tobacco wastes with which the charged. a

A dust filter I5 is connected at one end by aplpe I to the cylinder I. The other end of the filter is connected to a condenser l6 by piping l1 controlled by a valve f 8. The outlet end of cylinder is the condenser I 6' is connected by a pipe l9, sight glass "and a pipe-2| to a receiver, which in turn is connected through a valve 24 to a storage tank 25, the outlet of which is connected through a valve 26 to piping 21 leading to the usual scrubbers and separators referred to above. A vacuum pump 28 is connected by pipingfl' to the upper end of the receiver, and is set in operation when dsired to draw the nicotine vapors from the drier I, through the condenserv l6 and the receiver into the discharge tank. 4

To eiiect the vacuum breaks-in the drier I the latter is connected by a series of pipes 29, 30, 3|,

and 32 to a manifold 33 which is connected through a valve 35 to a source of dry superheated steam. This system is to be provided with as many pipes connected to the manifold as may be found necessary to effect substantially instantaneous break in the vacuum upon theoperation of the valve 35. The heat imparted to the cylincler through the steam in the jacket 4 and through the superheated steam imparted thereto during the vacuum break through the valve 35, must be such as to prevent condensation of the vapors within the cylinder I.

Upon the completion of the extraction of'nicotine from the tobacco scrap, the dry finely divided tobacco residue is removed from the drier,

, in condition for use as a fertilizer,,or as a base for stock feeds.

What I claim is:

l. The process of extracting nicotine from tobacco material which consists in mixing the material with an alkali, saturating the mixed material, heating the saturated mixture at .-atmospheric pressure to cause collapse of nicotine cells and to vaporize liquid contents.of the mixture,

reducing the pressure on the heated mixture to create a vacuum to effect expansion and rupture of the collapsed cells, condensing the vapors \in-.

der said reduced pressure, restoring and reducing the pressure in alternation on the residue, and condensing the vapors from the residue after each reduction in pressure, each restoration of pressure being eflected by breaking the vacuum with steam as suddenly as possible to cause collapse of unexplcded cellsin the heated and vaporized residue, and each reduction in pressure expanding and exploding the cells so collapsed.

,2. The process of extracting nicotine from tobacco material which consists in mixing the material with an alkali, saturating-the mixed material, heating the saturated mixture at pressure I not less than atmospheric to cause collapse of nicotine cells and vaporize liquid contents of the mixture at a temperature sufllcient to prevent condensation in the mixture, reducing the pressure on the heated mixtureto create a vacuum and thereby ei'fect expansion and rupture of the collapsed cells, condensing the vapors under the reduced pressure, restoring and reducing the pressure in alternation on the residue, while maintaining the latter at vaporizing temperature, and condensing the vapors from the residue after each reduction in pressure, each restoration of pressure being effected by breaking the vacuum with steam as suddenly as possible to cause collapse of the exploded cells in the heated and vaporized residue, and each reductionin pressure expanding and exploding thecells so collapsed.

3. The process of extracting nicotine from tobacco material which consists in mixing the material with arr alkali saturating the mixed material, heating the saturated mixture at pressure not less than atmospheric to cause collapse of nicotine cells and vaporize liquid contents of the mixture at a temperature sufllcient to prevent condensation in the mixture, reducing the pressure on the heated mixture to create a vacuum and thereby effect expansion and rupture of the collapsed cells, condensing the vapors under the reduced pressure, restoring and reducing the pressure in alternation on the residue, while maintaining the latter at vaporizing temperature, and condensing the vapors from the residue after'each reduction in pressure, each restoration of pressure being effected by breaking the vacuum with steam as suddenly as possible to cause collapse of the exploded cells in the heated and vaporized residue, and each reduction in pressure expanding.and exploding the cells so collapsed, the pressure variations being repeated in alternation until all the separable nicotine has been extracted from the material.

' ROBERT J. HYATT. 

